1. Field of the Invention
The invention relates to a terminal-modified conjugated diene-vinyl aromatic copolymer and method for manufacturing the same, and more particularly to a terminal-modified conjugated diene-vinyl aromatic copolymer highly compatible with silica and a method for manufacturing the same.
2. Description of the Related Art
Terminal-modified conjugated diene-vinyl aromatic copolymer can be used as a material for manufacturing tires. For tiress, rolling resistance and wet traction are crucial factors to save energy consumption and increase driving safety. Currently, carbon black is added to the conjugated diene-vinyl aromatic copolymer to increase the strength of the tires. In recent years, due to the depletion of oil resource and the global warming issue, the tire industries replace carbon black with silica with an aim of improving the rolling resistance of the tires and therefore reduce energy loss. In comparison with carbon black, silica is more difficult to be uniformly distributed in conjugated diene-vinyl aromatic copolymer. Therefore, the compatibility between silica and conjugated diene-vinyl aromatic copolymer needs to be further increased. According to one improvement method, when adding silica to terminal-modified conjugated diene-vinyl aromatic copolymer during the manufacturing process of tires, a modifier is used to perform blending. However, since the blending uniformity largely affects the properties of the products, product quality may differ from batch to batch, and quality reproducibility is poor. According to another method, a modifier such as a urea compound is added after terminal-modified conjugated diene-vinyl aromatic copolymer is polymerized so that the terminal-modified conjugated diene-vinyl aromatic copolymer reacts with the modifier for increasing compatibility between the terminal-modified conjugated diene-vinyl aromatic copolymer and silica. However, urea compounds are toxic and thus unfavorable to the production employees. Therefore, how to provide a terminal-modified conjugated diene-vinyl aromatic copolymer with silica well distributed in and a method for manufacturing the same has become a prominent task for the industries.